Capacity-variable type swash plate compressor

ABSTRACT

A capacity-variable type swash plate compressor in which the preferable operability of a link mechanism and reduction of manufacturing cost are realized is provided. According to the compressor in the present invention, a link mechanism includes one swash plate arm and intermediate arms. The intermediate arms include first and second intermediate arms. The first and second intermediate arms are joined while being rotatably supported by a lug member and the swash plate arm via a lug-side pin which constitutes a lug-side axis and a swash-plate-side pin which constitutes a swash-plate-side axis and clamping the lug member and the swash plate arm via the lug-side pin and the swash-plate-side pin so as to allow a sliding movement.

This application claims the benefit of priority to Japanese Patent Application No. 2007-259413, filed on Oct. 3, 2007, and Japanese Patent Application No. 2008-107735, filed on Apr. 17, 2008, these contents of which are hereby incorporated herein by reference.

BACKGROUND OF THE INVENTION

The present invention relates to a capacity-variable type swash plate compressor.

In the related art, a capacity-variable type swash plate compressor disclosed in JP-A-10-176658 is known. This compressor includes a housing which is composed of a cylinder block, a front housing, and a rear housing, and the cylinder block includes a plurality of cylinder bores penetrated therethrough. The rear housing includes a suction chamber and a discharge chamber which communicates with the respective cylinder bores via a valve unit. A crank chamber is defined by the front housing and the cylinder block, and a drive shaft is rotatably supported by the front housing and the cylinder block. In the crank chamber, a lug plate is fixed to the drive shaft, and a thrust bearing is provided between the lug plate and the front housing.

In the crank chamber, a swash plate is supported by the drive shaft so as to be capable of changing in angle of inclination, and a link mechanism is provided between the lug plate and the swash plate. The link mechanism includes first and second lug arms 91 a and 91 b being integrated with the lug plate 91 and projecting toward the swash plate 92, one swash plate arm 92 a being integrated with the swash plate 92 and projecting toward the lug plate 91, a first intermediate arm 93 provided between the first lug arm 91 a and the swash plate arm 92 a, and a second intermediate arm 94 provided between the second lug arm 91 b and the swash plate arm 92 a as shown in FIG. 37.

The first and second intermediate arms 93 and 94 are rotatably supported by the first and second lug arms 91 a and 91 b via a bolt 95, and by the swash plate arm 92 a via a pin 96. The bolt 95 extends in the direction of a lug-side axis A1 extending orthogonally to a virtual plane P which is defined by a center axis O of the drive shaft and the top dead center position of the swash plate 92. The pin 96 extends in the direction of a swash-plate-side axis A2 extending in parallel to the lug-side axis A1.

Pistons are stored in the respective cylinder bores so as to be capable of reciprocating therein, and the respective pistons each are formed with a compression chamber in the cylinder bore. Provided between the swash plate 92 and each piston is a movement converting mechanism. Specifically, the movement converting mechanism includes a rocking plate provided on the swash plate 92 on the side of the each piston, a bearing which is provided between the swash plate 92 and the rocking plate and only allows the rocking plate to rock according to the angle of inclination of the swash plate 92, and a piston rod for connecting the rocking plate and the each piston.

In this compressor, when the swash plate 92 rotates in association with driving of the driving shaft, the each piston reciprocates in the cylinder bore via the rocking plate and the each piston rod, whereby refrigerant gas is taken from the suction chamber into the compression chamber, is compressed therein, and then is discharged into the discharge chamber. Meanwhile, the movement converting mechanism converts the rocking movement of the swash plate 92 into the reciprocal movement of the piston. The link mechanism allows the swash plate 92 to change in angle of inclination with respect to the drive shaft and prohibits the swash plate 92 to rotate with respect to the drive shaft.

However, the compressor in the related art as described above, the first and second intermediate arms 93 and 94 include guided surfaces 93 a, 93 b, 94 a, and 94 b in front and back in the direction of rotation of the drive shaft respectively, the both guided surfaces 93 a and 93 b of the first intermediate arm 93 are guided by the inner surface of the first lug arm 91 a and one side surface of the swash plate arm 92 a, and the both guided surfaces 94 a and 94 b of the second intermediate arm 94 are guided by the inner surface of the second lug arm 91 b and the other surface of the swash plate arm 92 a. Therefore, in this compressor, accurate machining is required to make the both inner surfaces of the first and second lug arms 91 a and 91 b oppose in parallel, the both guided surfaces 93 a and 93 b of the first intermediate arm 93 face back to back in parallel, the both guided surfaces 94 a and 94 b of the second intermediate arm 94 face back to back in parallel, and both side surfaces of the swash plate arm 92 a face back to back in parallel. Otherwise, generation of abnormal sounds, impairment of capacity controllability due to failure of smooth movement of the link mechanism, or impairment of durability due to abrasion of the link mechanism may be resulted. Therefore, in this compressor, labors to manufacture components of the link mechanism with high degree of accuracy and to select the components before assembly are required, which causes appreciation of manufacturing cost. These disadvantages are also applicable to a compressor disclosed in JP-A-2003-172333 and a compressor disclosed in JP-A-2005-299516.

In the compressor described above, although the first and second intermediate arms 93 and 94 are rotatably supported via the bolt 95 and the pin 96, they are not coupled with each other. Therefore, in this compressor, the first and second intermediate arms 93 and 94 are capable of moving independently, so that the first and second intermediate arms 93 and 94 and thus the swash plate 92 are liable to be displaced from the normal position and distorted. In this case as well, the link mechanism is subject to wear and hence the durability of the compressor is periclitated. In this compressor, the first and second lug arms 91 a and 91 b are projected significantly toward the swash plate 92 with the sacrifice of manufacture of the lug plate 91 in order to restrain the distortion of the first and second intermediate arms 93 and 94 as described above. However, this means is still insufficient to restrain the distortion.

BRIEF SUMMARY OF THE INVENTION

In view of such circumstances, it is an object of the present invention to provide a capacity-variable type swash plate compressor which is capable of realizing the preferable operability of a link mechanism and reduction of the manufacturing cost.

A capacity-variable type swash plate compressor in the present invention comprises: a housing having a cylinder bore; a drive shaft rotatably supported by the housing; a lug member which rotates synchronously with the drive shaft in the housing; a swash plate supported by the drive shaft so as to change in angle of inclination in the housing; a link mechanism provided between the lug member and the swash plate in the housing so as to allow the swash plate to change in the angle of inclination with respect to the drive shaft and prohibit the swash plate from rotating with respect to the drive shaft; a piston stored in the cylinder bore so as to be capable of a reciprocal movement; and a movement converting mechanism provided between the swash plate and the piston for converting the rocking movement of the swash plate into the reciprocal movement of the piston.

The link mechanism includes one swash plate arm projecting from the swash plate toward the lug member, and intermediate arms rotatably supported by the lug member so as to rotate about the lug-side axis extending orthogonally to a virtual plane defined by the center axis of the drive shaft and the top dead center position of the swash plate and rotatably supported by the swash plate arm about the swash-plate-side axis which extends in parallel to the lug-side axis.

The intermediate arms include a first intermediate arm and a second intermediate arm extending from the lug member side to the swash plate side.

The first intermediate arm and the second intermediate arm are joined while being rotatably supported by the lug member and the swash plate arm via a lug-side pin which constitutes the lug-side axis and the swash-plate-side pin which constitutes the swash plate-side-axis and clamping the lug member and the swash plate arm via the lug-side pin and the swash-plate-side pin so as to allow the sliding movement.

According to the compressor in the present invention, the first and second intermediate arms are joined while clamping the lug member and the swash plate arm so as to allow a rocking movement by the lug-side pin and the swash-plate-side pin. Then, the inner surface of the first intermediate arm is guided by the outer surface of the lug member and the one side surface of the swash plate arm, and the inner surface of the second intermediate arm is guided by the outer surface of the lug member and the other side surface of the swash plate arm. In this manner, with this compressor, generation of abnormal sounds is avoided, and the link mechanism is smoothly operated. With this compressor, the accuracy of machining of the parallel surfaces of the lug member, the swash plate arm, and the first and second intermediate arms may be lowered, and necessity to select the components strictly for assembly is eliminated, so that reduction of the manufacturing cost is realized.

According to the compressor in the present invention, since the first and second intermediate arm are integrally joined via the lug-side pin and the swash-plate-side pin, the first and second intermediate arms do not move independently, and hence the first and second intermediate arms and thus the swash plate are not displaced from the normal positions and are hardly distorted. According to the compressor in the present invention, since the necessity of forming the lug arm on the lug member is eliminated, manufacture of the lug member and thus of the entire compressor is simplified.

Therefore, the capacity-variable type swash plate compressor according to the present invention is able to realize the preferable operability of the link mechanism and the reduction of manufacturing cost. The preferable operability of the link mechanism leads to the superior capacity controllability and the superior durability of the compressor.

Other aspects and advantages of the invention will be apparent from embodiments disclosed in the attached drawings, illustrations exemplified therein, and the concept of the invention.

BRIEF DESCRIPTION OF THE SEVERAL VIEWS OF THE DRAWINGS

The invention will be described in more detail along with the concept and advantages thereof by referring to the attached drawings and the detailed description of the preferred embodiments below.

FIG. 1 is a vertical cross-sectional view of a compressor according to Embodiment 1.

FIG. 2 is a perspective view of a link mechanism of the compressor according to Embodiment 1.

FIG. 3 is a schematic vertical cross-sectional view of the link mechanism of the compressor according to Embodiment 1.

FIG. 4 is a schematic lateral cross-sectional view of the link mechanism of the compressor according to Embodiment 1.

FIG. 5 is a schematic vertical cross-sectional view of the link mechanism of the compressor according to Embodiment 2.

FIG. 6 is a schematic lateral cross-sectional view of the link mechanism of the compressor according to Embodiment 2.

FIG. 7 is a schematic vertical cross-sectional view of the link mechanism of the compressor according to Embodiment 3.

FIG. 8 is a schematic side view of the link mechanism of the compressor according to Embodiment 4.

FIG. 9 is a schematic side view of the link mechanism of the compressor according to Embodiment 5.

FIG. 10 is a schematic side view of the link mechanism of the compressor according to Embodiment 6.

FIG. 11 is a schematic lateral cross-sectional view of the link mechanism of the compressor according to Embodiment 7.

FIG. 12 is a schematic lateral cross-sectional view of the link mechanism of the compressor according to Embodiment 8.

FIG. 13 is a schematic side view of the link mechanism of the compressor according to Embodiment 9.

FIG. 14 is a schematic side view of the link mechanism of the compressor according to Embodiment 10.

FIG. 15 is a schematic side view of the link mechanism of the compressor according to Embodiment 11.

FIG. 16 is a schematic side view of the link mechanism of the compressor according to Embodiment 12.

FIG. 17 is a schematic lateral cross-sectional view of the link mechanism of the compressor according to Embodiment 12.

FIG. 18 is a schematic side view of the link mechanism of the compressor according to Embodiment 13.

FIG. 19 is a schematic lateral cross-sectional view of the link mechanism of the compressor according to Embodiment 13.

FIG. 20 is a schematic side view of the link mechanism of the compressor according to Embodiment 14.

FIG. 21 is a schematic lateral cross-sectional view of the link mechanism of the compressor according to Embodiment 14.

FIG. 22 is a schematic side view of the link mechanism of the compressor according to Embodiment 15.

FIG. 23 is a schematic lateral cross-sectional view of the link mechanism of the compressor according to Embodiment 15.

FIG. 24 is a schematic lateral cross-sectional view of the link mechanism of the compressor according to Embodiment 16.

FIG. 25 is a schematic lateral cross-sectional view of the link mechanism of the compressor according to Embodiment 17.

FIG. 26 is a schematic lateral cross-sectional view of the link mechanism of the compressor according to Embodiment 17.

FIG. 27 is a schematic lateral cross-sectional view of the link mechanism of the compressor according to Embodiment 18.

FIG. 28 is a schematic cross-sectional view of the link mechanism of the compressor according to Embodiment 19 taken along the plane perpendicular to the axis.

FIG. 29 is a schematic cross-sectional view of the link mechanism of the compressor according to Embodiment 20.

FIG. 30 is a schematic side view of the link mechanism of the compressor according to Embodiment 21.

FIG. 31 is a schematic side view of the link mechanism of the compressor according to Embodiment 22.

FIG. 32 is a schematic side view of the link mechanism of the compressor according to Embodiment 23.

FIG. 33 is a schematic lateral cross-sectional view of the link mechanism of the compressor according to Embodiment 23.

FIG. 34 is a schematic lateral cross-sectional view of the link mechanism of the compressor according to Embodiment 24.

FIG. 35 is a schematic lateral cross-sectional view of the link mechanism of the compressor according to Embodiment 25.

FIG. 36 is a schematic lateral cross-sectional view of the link mechanism of the compressor according to Embodiment 26.

FIG. 37 is a schematic lateral cross-sectional view of the link mechanism of the compressor in the related art.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

Referring now to the drawings, Embodiments 1 to 26 in which the present invention is embodied will be described below.

Embodiment 1

According to a capacity-variable type swash plate compressor in Embodiment 1, as shown in FIG. 1, a housing includes a cylinder block 1, the front housing 2, and a rear housing 4, a front housing 2 is joined to the front end of the cylinder block 1, and the rear housing 4 is joined to the rear end of the cylinder block 1 via a valve unit 3. The cylinder block 1 and the front housing 2 are formed with shaft holes 1 a and 2 a extending in the axial direction so as to penetrate therethrough, and a drive shaft 6 is rotatably supported in the shaft holes 1 a and 2 a via the radial bearings 5 a and 5 b and a shaft seal device 5 c. The left side in FIG. 1 corresponds to the front side, and the right side thereof corresponds to the rear side.

The front housing 2 and the cylinder block 1 define a crank chamber 7. A lug plate 8 is fixed to the drive shaft 6 in the crank chamber 7. As shown in FIGS. 2 to 4 as well, the lug plate 8 is formed with a press-fitting hole 8 a, and the drive shaft 6 is press-fitted into the press-fitting hole 8 a. The lug plate 8 integrally includes a thrust plate 9 and a lug member 10. The lug plate 8 contributes to reduction of manufacturing cost of the compressor because it is obtained by improving lug plates having a lug arm, which have been used in the related art relatively easily.

The thrust plate 9 is formed into a disk shape, and a thrust bearing 5 d is provided between the thrust plate 9 and the front housing 2. As shown in FIG. 2, the thrust plate 9 is formed with a weight portion 9 a on the outer periphery thereof on the side of the top dead center.

The lug member 10 is formed into a horseshoe shape having parallel surfaces 10 a extending in parallel to each other facing back to back on the side of the bottom dead center. As shown in FIG. 4, the lug member 10 is formed with an insertion hole 10 b extending orthogonally to the both parallel surfaces 10 a on the side of the bottom dead center. The insertion hole 10 b is formed to have a diameter slightly larger than that of the lug-side pin 23, described later.

As shown in FIG. 1, the crank chamber 7 is provided with a swash plate 11 on the back side of the lug plate 8. The swash plate 11 is formed with a flat shoe sliding surface 11 a on the front and rear outer peripheral surfaces on the side of the outer periphery thereof. The drive shaft 6 is penetrated through the swash plate 11 and, in this state, the swash plate 11 is adapted to change in angle of inclination by a link mechanism 12 provided between the swash plate 11 and the lug member 10. As shown in FIG. 2 and FIG. 3, one supporting portion 11 e projects from the surface of the swash plate 11 on the side of the lug member 10 and on the side of the bottom dead center position thereof toward the lug member 10, and the supporting portion 11 e is adapted to come into abutment with the rear surface of the lug member 10 when the swash plate 11 is inclined to a maximum angle of inclination.

As shown in FIG. 1, the cylinder block 1 is formed with a plurality of cylinder bores 1 b extending therethrough in the axial direction and being arranged in a concentric pattern. A single-head piston 13 is stored in each cylinder bore 1 b so as to be capable of a reciprocal movement. The each piston 13 includes shoe receiving surfaces 13 a at the neck portion thereof so as to be depressed in a spherical surface and to face to each other. A pair of front and rear shoes 14 are provided between the swash plate 11 and the each piston 13. The each shoe 14 is formed substantially into a semi-spherical shape. The front and rear shoe sliding surfaces 11 a, the front and rear shoe receiving surfaces 13 a, and the front and rear shoes 14 constitute a movement converting mechanism.

An urging spring 27 which urges the swash plate 11 so as to reduce the angle of inclination is provided between the lug member 10 and the swash plate 11. A snap ring 28 a is provided on the drive shaft 6 on the back side of the urging spring 27, and a restoring spring 28 b for urging the swash plate 11 so as to increase the angle of inclination is provided on the front side of the snap ring 28 a.

A rear chamber 1 c is formed at the rear end of the cylinder block 1 coaxially with the shaft hole 1 a. In the rear chamber 1 c, a thrust bearing 29 a is provided at the rear end of the drive shaft 6, and a pressing spring 29 b is provided between the thrust bearing 29 a and the valve unit 3. The urging spring 27, the restoring spring 28 b, and the pressing spring 29 b are coil springs.

The rear housing 4 includes a suction chamber 4 a and a discharge chamber 4 b formed therein. The cylinder bores 1 b are adapted to be capable of communicating with the suction chamber 4 a via a suction valve mechanism of the valve unit 3, and of communicating with the discharge chamber 4 b via a discharge valve mechanism of the valve unit 3.

The rear housing 4 includes a capacity control valve 15 stored therein. The capacity control valve 15 communicates with the suction chamber 4 a via a detection channel 4 c, and causes the discharge chamber 4 b and the crank chamber 7 to communicate with each other via an air-supply channel 4 d, which is shown only partly. The capacity control valve 15 changes the opening of the air-supply channel 4 d and changes the amount of discharge of the compressor by detecting the pressure in the suction chamber 4 a. The crank chamber 7 and the suction chamber 4 a communicate with each other via an air-bleeding channel, not shown. A condenser 17, an expansion valve 18, and an evaporator 19 are connected to the discharge chamber 4 b via a piping 16, and the evaporator 19 is connected to the suction chamber 4 a via the piping 16.

As shown in FIGS. 2 to 4, the link mechanism 12 includes one swash plate arm 11 b formed integrally with the swash plate 11 and projecting toward the lug plate 8 on the side of the top dead center, and intermediate arms 20 which clamps the lug member 10 and the swash plate arm 11 b. The intermediate arms 20 includes plate-shaped first and second intermediate arms 21 and 22 extending from the lug member 10 side to the swash plate 11 side, a lug-side pin 23, and a swash-plate-side pin 24.

As shown in FIG. 4, the first intermediate arm 21 includes an outer surface 21 a and an inner surface 21 b, which extend in parallel to with a virtual plane P defined by the center axis O of the drive shaft 6 and the position of the top dead center position of the swash plate 11 and face back to back in pair, on the front and back in the direction of rotation R of the drive shaft 6. The second intermediate arm 22 includes an outer surface 22 a and an inner surface 22 b, which extend in parallel to the virtual plane P and face back to back in pair, on the front and back in the direction of rotation R of the drive shaft 6.

The first intermediate arm 21 includes press-fitting holes 21 c and 21 d penetrated therethrough at both ends thereof so as to extend at a right angle with respect to the outer surface 21 a and the inner surface 21 b, and the second intermediate arm 22 includes press-fitting holes 22 c and 22 d penetrated therethrough at both ends thereof so as to extend at a right angle with respect to the outer surface 21 a and the inner surface 22 b. The press-fitting holes 21 c and 22 c each include a press-fitting margin with respect to the lug-side pin 23, described later, and the press-fitting holes 21 d and 22 d each include a press-fitting margin with respect to the swash-plate-side pin 24, described later.

As shown in FIG. 2, the swash plate arm 11 b is formed to have almost the same width as the distance between the both parallel surfaces 10 a of the lug member 10, and includes parallel surfaces 11 c which extend in parallel and faces back to back. The swash plate arm 11 b is formed with an insertion hole 11 d which extends orthogonally to the both parallel surfaces 11 c so as to penetrate therethrough. The insertion hole 11 d is formed to have a diameter slightly larger than that of a swash-plate-side pin 24, described later.

The insertion hole 10 b of the lug member 10 and the press-fitting holes 21 c and 22 c of the first and second intermediate arms 21 and 22 extend in the direction of a lug-side axis A1 which extends orthogonally to the virtual plane P as shown in FIG. 4. The insertion hole 11 d of the swash plate arm 11 b and the press-fitting holes 21 d and 22 d of the first and second intermediate arms 21 and 22 extend in the direction of a swash-plate-side axis A2 which extends in parallel to the lug-side axis A1. As shown in FIG. 3, the swash-plate-side axis A2 is positioned on the side of the top dead center position of the swash plate 11 and the lug-side axis A1 is closer to the drive shaft 6 in comparison with the swash-plate-side axis A2.

The first and second intermediate arms 21 and 22 are joined while being rotatably supported by the lug member 10 and the swash plate arm 11 b via the lug-side pin 23 and the swash-plate-side pin 24 and clamping the lug member 10 and the swash plate arm 11 b via the lug-side pin 23 and the swash-plate-side pin 24 so as to allow the sliding movement. More specifically, the lug-side pin 23 is loosely fitted to the lug member 10 and is press-fitted into the first and second intermediate arms 21 and 22, and the swash-plate-side pin 24 is loosely fitted to the swash plate arm 11 b and is press-fitted into the first and second intermediate arms 21 and 22. The lug-side pin 23 constitutes the lug-side axis A1 and the swash-plate-side pin 24 constitutes the swash-plate-side axis A2. The swash plate arm 11 b is formed so as to avoid the position vertically above the shoe sliding surface 11 a.

The link mechanism 12 as described above is assembled in the following manner. First of all, the drive shaft 6, the lug plate 8, the swash plate 11, the first and second intermediate arms 21 and 22, the lug-side pin 23, and the swash-plate-side pin 24 are prepared. The first and second intermediate arms 21 and 22 are the same plate members having no difference between the front and the rear, and the right side and the back side, and the lug-side pin 23 and the swash-plate-side pin 24 are the same pins having no difference between the left and the right.

The lug plate 8 is press-fitted to the drive shaft 6, and the drive shaft 6 is inserted into the swash plate 11. Then, the lug-side pin 23 and the swash-plate-side pin 24 are press-fitted into the respective press-fitting holes 21 c and 21 d of the first intermediate arm 21 and, in this state, the lug-side pin 23 and the swash-plate-side pin 24 are inserted into the insertion holes 10 b and 11 d of the lug member 10 and the swash plate arm 11 b, respectively, and, simultaneously, the lug-side pin 23 and the swash-plate-side pin 24 are press-fitted into the press-fitting holes 22 c and 22 d of the second intermediate arm 22.

In this case, since the first and second intermediate arms 21 and 22 have no difference between the front and the back, and the right side and the back side, and the lug-side pin 23 and the swash-plate-side pin 24 are the same pins, the insertion holes 10 b and 11 d have the same diameter, and the press-fitting holes 21 c, 21 d, 22 c, and 22 d have the same diameter, a high productivity is demonstrated. Since the first intermediate arm 21 comes into contact with the lug member 10 and the swash plate arm 11 b at a high pressure, grease is applied to the first intermediate arm 21, the lug member 10 and the swash plate arm 11 b to avoid the same from being adhered to each other. The grease serves to secure a minute gap between the first intermediate arm 21, the lug member 10, and the swash plate arm 11 b. It is also possible to secure a minute gap by forming a thin film of coating which is easily worn by the sliding movement in advance on the first intermediate arm 21 or the lug member 10 and the swash plate arm 11 b. When the first and second intermediate arms 21 and 22 clamp the lug member 10 or the swash plate arm 11 b, the press-fitting operation is ended.

In this manner, the first and second intermediate arms 21 and 22 are joined to each other while being guided preferably with reduced dimensional tolerance with respect to the lug member 10 and the swash plate arm 11 b. Means for preventing the lug-side pin 23 and the swash-plate-side pin 24 from coming apart is not necessary. Accordingly, a high productivity is demonstrated. With the procedure shown thus far, a sub-assembly including the drive shaft 6, the lug plate 8, the link mechanism 12, and the swash plate 11 is assembled. After having assembled, the grease is removed by heating, so that the link mechanism 12 is obtained. The compressor is assembled with the link mechanism 12.

In the compressor configured as described above, the lug plate 8 and the swash plate 11 rotate synchronously by the drive shaft 6 being driven in the direction of rotation R, and the pistons 13 reciprocate in the cylinder bores 1 b via the shoes 14. Accordingly, the compression chambers defined on the head sides of the pistons 13 are changed in capacity. Therefore, refrigerant gas in the suction chamber 4 a is taken into the compression chambers and is compressed, and then is discharged into the discharge chamber 4 b. In this manner, a refrigerating action is carried out in a refrigerating circuit including the compressor, the condenser 17, the expansion valve 18, and the evaporator 19. Meanwhile, the movement converting mechanism converts the rocking movement of the swash plate 11 into the reciprocal movement of the pistons 13. The link mechanism 12 allows the swash plate 11 to change in angle of inclination with respect to the drive shaft 6 and prohibits the swash plate 11 from rotating with respect to the drive shaft 6. In particular, in this compressor, since the lug-side axis A1 is located on the side of the bottom dead center position of the swash plate 11 and the swash-plate-side axis A2 is located on the side of the top dead center position of the swash plate 11, the balance of rotation is easily achieved, so that the weight portion of the swash plate 11 is not necessary. Therefore, the weight reduction and the reduction in number of machining processes are realized.

In this compressor, the first and second intermediate arms 21 and 22 are joined while clamping the lug member 10 and the swash plate arm 11 b via the lug-side pin 23 and the swash-plate-side pin 24 so as to allow the sliding movement. The inner surface 21 b of the first intermediate arm 21 is guided by the parallel surfaces 10 a of the lug member 10 and the parallel surfaces 11 c of the swash plate arm 11 b, and the inner surface 22 b of the second intermediate arm 22 is guided by the parallel surfaces 10 a of the lug member 10 and the parallel surfaces 11 c of the swash plate arm 11 b. Therefore, in this compressor, abnormal sounds are not generated, and the link mechanism 12 operates smoothly. With this compressor, the accuracy of machining of the parallel surfaces of the lug member 10, the swash plate arm 11 b, and the first and second intermediate arms 21 and 22 may be lowered, and necessity to select the component strictly for assembly is eliminated, so that reduction of manufacturing cost is realized.

In this compressor, the first and second intermediate arms 21 and 22 are jointed via the lug-side pin 23 and the swash-plate-side pin 24, and are configured into the integral intermediate arms 20. Therefore, the first and second intermediate arms 21 and 22 are not moved independently, and the first and second intermediate arms 21 and 22 and thus the swash plate 11 are not displaced from the normal positions, and is hardly distorted. In this compressor, since the necessity of forming the lug arm on the lug member 10 is eliminated, manufacture of the lug member 10 and thus of the entire compressor is simplified.

Therefore, this compressor is able to realize the preferable operability of the link mechanism 12 and the reduction of the manufacturing cost. The preferable operability of the link mechanism 12 leads to demonstration of the superior capacity controllability and superior durability of the compressor.

In this compressor, since the intermediate arms 20 is rotatably supported as described above, the link mechanism 12 approaches the drive shaft 6. Therefore, the lubricating oil in the crank chamber 7 is hardly stirred, and hence is hardly heated. Therefore, the viscosity of the lubricating oil is hardly lowered, and hence the high sliding property is secured. A rubbery material such as a shaft seal device 5 c is hardly deteriorated due to the heat of the lubricating oil, so that the high durability is demonstrated. Since the intermediate arms 20 is rotatably supported in this manner, the center of gravity of the intermediate arms 20 is low, and hence the centrifugal force is reduced. Therefore, a load in the direction to increase the angle of inclination of the swash plate 11 at a high velocity is reduced, and hence the angle of inclination of the swash plate 11 is easily controlled.

In this compressor, there is one such the swash plate arm 11 b, and the swash plate arm 11 b is formed so as to avoid a position vertically above the shoe sliding surface 11 a. Therefore, it is easy to form the swash plate 11 as an integrated member, and to machine the shoe sliding surface 11 a. This is an advantageous point against the compressor disclosed, for example, in JP-A-2005-299516.

Embodiment 2

The compressor in Embodiment 2 employs a link mechanism 30 as shown in FIG. 5 and FIG. 6. In the link mechanism 30, an outer spline 31 a is formed on a drive shaft 31, and an inner spline 32 a is formed on a thrust plate 32, and the outer spline 31 a and the inner spline 32 a are fitted to each other. In this manner, the thrust plate 32 is clearance-fitted to the drive shaft 31.

The thrust plate 32 is formed of vibration-control metal alloy. The lug member 33 is formed separately from the thrust plate 32, and comes into abutment with the thrust plate 32. A lug member 33 is formed with a press-fitting hole 33 a, and the drive shaft 31 is press-fitted into the press-fitting hole 33 a. Other configurations are the same as in Embodiment 1.

In this compressor, the thrust plate 32 and the lug member 33 are formed separately, and the thrust plate 32 comes into abutment with the lug member 33. Therefore, the thrust plate 32 does not have a function to rotate the swash plate 11 synchronously, and has a function to give a compression reaction force. Therefore, the thrust plate 32 does not involve the link mechanism 30, and hence the strength or the hardness of portions between the insertion holes 10 b and 11 d and the lug-side pin 23 or the swash-plate-side pin 24 is not necessary. Therefore, the demands of weight reduction or request of improvement of the noise due to the torque variations may be met independently only by changing the material mainly of the thrust plate 32.

In this compressor, since the thrust plate 32 is clearance-fitted to the drive shaft 31, vibrations or abnormal sounds due to the inclination of the seat of the front housing 2 which receives the thrust bearing 5 d and the tolerance of perpendicularity between the thrust plate 32 and the drive shaft 31 may also be solved.

In the compressor, since the thrust plate 32 is clearance-fitted to the drive shaft 31, the thrust plate 32 by itself is inclined by the compression reaction force and hence the deviated abutment against the thrust bearing 5 d is avoided. Therefore, the thrust bearing 5 d having a small load capacity may be employed, and the diameter of the thrust plate 32 may be reduced, so that the reduction of manufacturing cost of the compressor and downsizing of the compressor are realized. Since the moment acting on the swash plate 11 is received by the radial bearings 5 a and 5 b, the thrust load is received at a substantially center of the thrust plate 32, so that the vibrations and abnormal sounds generated at the radial bearings 5 a and 5 b and the thrust bearing 5 d are reduced. With the reduction of the diameter of the thrust plate 32 and the thrust bearing 5 d, the lubricating oil in the crank chamber 7 is hardly stirred, and hence heat generation of the lubricating oil may be restrained. Other effects and advantages are the same as in Embodiment 1.

Embodiment 3

The compressor in Embodiment 3 employs a link mechanism 40 shown in FIG. 7. In the link mechanism 40, part of a drive shaft 41 is used as a lug member 41 a. Other configurations are the same as in Embodiment 2.

In this compressor, control of the press-fitting margin required for press-fitting the lug member 41 a into the drive shaft 41 is eliminated. In this compressor, a labor to machine the seat of the thrust plate 32 after having assembled the sub-assembly including the drive shaft 41 (lug member 41 a), the thrust plate 32, the link mechanism 40, and the swash plate is eliminated. Other effects and advantages are the same as in Embodiment 2.

Embodiment 4

The compressor in Embodiment 4 employs a link mechanism 50 shown in FIG. 8. In the link mechanism 50, the swash plate 11 does not have the supporting portion 11 e, and the thrust plate 9 of the lug plate 8 is formed with supporting members 9 b. The supporting members 9 b project from the surface of the thrust plate 9 on the side of the swash plate 11 and on the side of the top dead center toward the swash plate 11 at two points and abut against the side surfaces of the first and second intermediate arms 21 and 22 on the side of the thrust plate 9 when the swash plate 11 is inclined to a maximum angle of inclination to support the first and second intermediate arms 21 and 22 on the side opposite from the swash plate. Other configurations are the same as in Embodiment 1.

In this compressor, the compression reaction force transferred from the pistons 13 to the swash plate 11 is received by the supporting members 9 b of the thrust plate 9, which is integrally formed with the lug member 10, so that the deformation of the link mechanism 50 is prevented and superior durability is demonstrated. In particular, in this compressor, since the lug-side axis A1 is positioned on the side of the bottom dead center position of the swash plate 11 and the swash-plate-side axis A2 is positioned on the side of the top dead center position of the swash plate 11, the compression reaction force acts on the side of the top dead center as a large load Fu. Therefore, by receiving the large load Fu by the supporting members 9 b on the side of the top dead center, downsizing of the first and second intermediate arms 21 and 22 and the swash-plate-side pin 24 and superior durability are achieved. Other effects and advantages are the same as in Embodiment 1.

Embodiment 5

The compressor in Embodiment 5 employs a link mechanism 60 shown in FIG. 9. In the link mechanism 60, the swash plate 11 does not have the supporting portion 11 e, and supporting portions 34 a are provided on the lug member 34, which is provided separately from the thrust plate 32. The supporting portions 34 a project from the side surface of the lug member 34 sideward at two points and abut against the side surfaces of the first and second intermediate arms 21 and 22 on the side of the top dead center position of the lug member 34 when the swash plate 11 is inclined to a maximum angle of inclination to support the first and second intermediate arms 21 and 22 on the opposite side of the swash plate. Other configurations are the same as in Embodiments 2 and 3.

In this compressor, the thrust plate 32 is clearance-fitted to the drive shaft 31, and the lug member 34 receives the compression reaction force transmitted from the pistons 13 to the swash plate 11 by the supporting portions 34 a. Other effects and advantages are the same as in Embodiments 2 and 3.

Embodiment 6

The compressor in Embodiment 6 employs a link mechanism 70 shown in FIG. 10. In the link mechanism 70, the first and second intermediate arms 21 and 22 each have a weight portion 22 e on the side of the bottom dead center position of the swash plate 11 (the weight portion of the first intermediate arm 21 is not shown). Other configurations are the same as in Embodiment 2.

In this compressor, the balance of rotation is achieved by the weight portion 22 e of the first and second intermediate arms 21 and 22. Other effects and advantages are the same as in the compressor in Embodiment 2.

Embodiment 7

The compressor in Embodiment 7 employs a link mechanism shown in FIG. 11. In the link mechanism 80, the thrust plate 32 provided separately from the lug member 33 is formed with a pair of side walls 35 and 36 extending toward the swash plate 11. The side walls 35 and 36 project until parts of them cover the both end surfaces of the swash-plate-side pin 24. The inner sides of the side walls 35 and 36 are formed with the guiding surfaces 35 a and 36 a for guiding the outer surface 21 a of the first intermediate arm 21 and the outer surface 22 a of the second intermediate arm 22. Other configurations are the same as in Embodiment 2.

In this compressor, since the thrust plate 32 clearance-fitted to the drive shaft 31 is formed with the side walls 35 and 36, the vibrations or abnormal sounds may be avoided irrespective of the tolerance such as the positional relation or symmetry of the thrust plate 32 and the drive shaft 31 or the lug member 33 only by forming the both guiding surfaces 35 a and 36 a of the side walls 35 and 36 with high degree of accuracy. Since the side walls 35 and 36 of the thrust plate 32 are able to reinforce the first and second intermediate arms 21 and 22, the thicknesses of the first and second intermediate arms 21 and 22 may be reduced, so that weight reduction and improvement of the balance of rotation of the link mechanism 80 are enabled. In addition, fixation of the lug-side pin 23 or the swash-plate-side pin 24 and the first and second intermediate arms 21 and 22 by the press-fitting is not necessarily required, and hence assembleability is improved. Other effects and advantages are the same as in the compressor in Embodiment 2.

Embodiment 8

The first and second intermediate arms are not limited to the plate-shaped members, and may be rod-shaped members. The width of the lug member does not have to be the same as the width of the swash plate arm. For example, as shown in FIG. 12, the width of the lug member 10 may be larger than the width of the swash plate arm 11 b. In this case, bent plate shaped or rod-shaped members may be used as the first and second intermediate arms 25 and 26.

Embodiment 9

According to the compressor in Embodiment 9, as shown in FIG. 13, the lug plate 8 includes the lug member 10 and the thrust plate 9 integrated with each other, and the lug plate 8 is press-fitted to the drive shaft 6. A leaf spring 37 is provided between the thrust plate 9 and the second intermediate arm 22 by being fixed thereto at both ends thereof. The urging spring 27 formed of a coil spring in Embodiment 1 shown in FIG. 1 is omitted. The leaf spring 37 has an urging force for urging the swash plate 11 in the direction to reduce the angle of inclination thereof. A leaf spring may be provided between the thrust plate 9 and the first intermediate arm 21. Other configurations are the same as in Embodiment 1.

In this compressor, the swash plate 11 is urged by the leaf spring 37 in the direction to reduce the angle of inclination, so that reduction of a torque for activation is achieved. With the employment of the leaf spring 37, the urging spring 27 in the related art may be eliminated, and hence the lug-side pin 23 may easily be positioned on the side of the bottom dead center position of the swash plate 11. Other effects and advantages are the same as in Embodiment 1.

Embodiment 10

According to the compressor in Embodiment 10, as shown in FIG. 14, the lug member 10 and a thrust plate 38 are separately provided. The thrust plate 38 is formed with an insertion hole 38 a so as to penetrate therethrough, and the drive shaft 6 is inserted into the insertion hole 38 a. In this manner, the thrust plate 38 is clearance-fitted to the drive shaft 6. Provided between the thrust plate 38 and the second intermediate arm 22 is the leaf spring 37 fixed to both members at the both ends thereof. The urging spring 27 formed of a coil spring in Embodiment 1 shown in FIG. 1 is omitted. A leaf spring may be provided between the thrust plate 38 and the first intermediate arm 21. Other configurations are the same as in Embodiment 9.

In this compressor as well, the same effects and advantages as in Embodiment 9 are achieved. Although the drive shaft 6 and the thrust plate 38 are not spline fitted to each other, the lug member 10 comes into abutment with the thrust plate 38 by a thrust load transmitted via the pistons 13, the shoes 14, the swash plate 11, the link mechanism 12, and the leaf spring 37, so that the thrust plate 38 rotates synchronously with the drive shaft 6.

Embodiment 11

The compressor in Embodiment 11, as shown in FIG. 15, a torsion coil spring 39 is provided between the second intermediate arm 22 and the swash plate arm 11 b. A coil portion 39 a of the torsion coil spring 39 is fitted on the swash-plate-side pin 24, and one end 39 b of the torsion coil spring 39 is fixed to the swash plate arm 11 b, and the other end 39 c of the torsion coil spring 39 is fixed to the second intermediate arm 22. The urging spring 27 made up of the coil spring in Embodiment 1 shown in FIG. 1 is omitted. A torsion coil spring may be provided between the lug member 10 and the second intermediate arm 22, between the first intermediate arm 21 and the swash plate arm 11 b, or between the lug member 10 and the first intermediate arm 21. Other configurations are the same as in Embodiment 9.

In this compressor as well, the same effects and advantages as in Embodiment 9 are achieved.

Embodiment 12

According to the compressor in Embodiment 12, as shown in FIGS. 16 and 17, a disk-shaped lug member 42 is press-fitted to the drive shaft 6. The lug member 42 is provided with the thrust bearing 5 d for receiving a thrust load on the front surface thereof between the lug member 42 and the front housing 2 (see FIG. 1), and the rear surface of the lug member 42 is formed with a lug arm 42 a projecting toward the swash plate 11. The lug arm 42 a is positioned on the side of the top dead center position of the swash plate 11.

The lug arm 42 a is formed with an insertion hole 42 b so as to penetrate therethrough, and the swash plate arm 11 b is formed with the insertion hole 11 d so as to penetrate therethrough. The lug-side pin 23 is inserted into the insertion hole 42 b and the swash-plate side pin 24 is inserted into the insertion hole 11 d. The first and second intermediate arms 21 and 22 are joined to each other while being rotatably supported by the lug arm 42 a and the swash plate arm 11 b via the lug-side pin 23 and the swash-plate-side pin 24 and clamping the lug arm 42 a and the swash plate arm 11 b so as to allow the sliding movement via the lug-side pin 23 and the swash-plate-side pin 24.

As shown in FIG. 17, run-offs 42 c are formed on both side surfaces of the lug arm 42 a so as to be away from the inner surfaces 21 b and 22 b of the first and second intermediate arms 21 and 22 as they go away from the insertion hole 42 b. The swash plate arm 11 b is formed with run-offs 11 f so as to be away from the inner surfaces 21 b and 22 b of the first and second intermediate arms 21 and 22 as they go away from the insertion hole 11 d. In the compressor in Embodiment 12, a link mechanism 43 is configured as described above. Other configurations are the same as in Embodiment 1.

In this compressor, the first and second intermediate arms 21 and 22 are integrated, and hence are hardly distorted from their original property. Even though there is a probability of occurrence of slight distortion due to the accumulated tolerance or the like, since the run-offs 42 c and 11 f are formed on the lug arm 42 a and the swash plate arm 11 b, distortion caused by the first and second intermediate arms 21 and 22 is avoided.

In this compressor, the lug member 42 and the swash plate 11 are slightly reduced in weight by the run-offs 42 c and 11 f formed on the lug arm 42 a and the swash plate arm 11 b, and hence the balance of rotation is easily maintained. Other effects and advantages are the same as in Embodiment 1.

Embodiment 13

According to the compressor in Embodiment 13, as shown in FIG. 18 and FIG. 19, a thrust plate 44 is formed with an insertion hole 44 a so as to penetrate therethrough and the drive shaft 6 is inserted though the insertion hole 44 a. In this manner, the thrust plate 44 is clearance-fitted to the drive shaft 6. The thrust plate 44 is provided with the thrust bearing 5 d for receiving a thrust load on the front surface thereof between the thrust plate 44 and the front housing 2 (see FIG. 1). Although the drive shaft 6 and the thrust plate are not spline fitted, the thrust plate 44 rotates synchronously with the drive shaft 6. A lug member 45 formed into a horseshoe shape is press-fitted to the drive shaft 6 on the back side of the thrust plate 44.

The lug member 45 is formed with an insertion hole 45 b so as to penetrate therethrough, and the swash plate arm 11 b is formed with the insertion hole 11 d so as to penetrate therethrough. The lug-side pin 23 is inserted into the insertion hole 45 b and the swash-plate-side pin 24 is inserted into the insertion hole 11 d. The first and second intermediate arms 21 and 22 are joined while being rotatably supported by the lug member 45 and the swash plate arm 11 b via the lug-side pin 23 and the swash-plate-side pin 24 and clamping the lug member 45 and the swash plate arm 11 b via the lug-side pin 23 and the swash-plate-side pin 24 so as to allow the sliding movement.

As shown in FIG. 19, run-offs 45 c are formed on both side surfaces of the lug member 45 so as to be away from the inner surfaces 21 b and 22 b of the first and second intermediate arms 21 and 22 as they go away from the insertion hole 45 b. The swash plate arm 11 b is formed with the run-offs 11 f so as to be away from the inner surfaces 21 b and 22 b of the first and second intermediate arms 21 and 22 as they go away from the insertion hole 11 d. According to the compressor in Embodiment 13, a link mechanism 46 is configured as described above. Other configurations are the same as in Embodiment 10.

With this compressor, the same effects and advantages are achieved as in Embodiment 12.

Embodiment 14

According to the compressor in Embodiment 14, as shown in FIG. 20 and FIG. 21, an integral lug plate 49 includes a lug member 47 and a thrust plate 48 integrated with each other, and the lug plate 49 is press-fitted to the drive shaft 6. The lug member 47 is formed with an insertion hole 47 a so as to penetrate therethrough, and the swash plate arm 11 b is formed with the insertion hole 11 d so as to penetrate therethrough.

In this compressor, two members 51 are used. The members 51 each include a plate shaped arm portion 51 a and a pin portion 51 b extending from one end of the arm portion 51 a at a right angle with respect to the arm portion 51 a. The arm portion 51 a is formed with a press-fitting hole 51 c so as to penetrate through the other end thereof.

The arm portion 51 a is a portion which may serve as any one of the first intermediate arm and the second intermediate arm, and has an outer surface 51 d and an inner surface 51 e facing back to back in pair. The pin portion 51 b is a portion which may serve as any one of the lug-side pin and the swash-plate-side pin, and is formed to have a diameter which is press-fitted into the press-fitting hole 51 c of the other members 51. According to the compressor in Embodiment 14, a link mechanism 52 is configured as described above. Other configurations are the same as in Embodiment 11.

In this compressor, a sub-assembly is obtained by assembling the two members 51 with the drive shaft 6, the lug plate 49, the swash plate 11, and so on. Accordingly, the number of components is reduced, and the number of press-fitting operations is reduced, so that the reduction manufacturing cost may be realized. Other effects and advantages are also achieved as in the same manner in Embodiment 1.

Embodiment 15

According to the compressor in Embodiment 5, as shown in FIG. 22 and FIG. 23, a thrust plate 53 is formed with an insertion hole 53 a, and the drive shaft 6 is inserted into the insertion hole 53 a so as to penetrate therethrough. In this manner, the thrust plate 53 is clearance-fitted to the drive shaft 6. The thrust plate 53 is provided with the thrust bearing 5 d for receiving the thrust load on the front surface thereof between the thrust plate 53 and the front housing 2 (see FIG. 1). Although the drive shaft 6 and the thrust plate 53 are not spline fitted, the thrust plate 53 rotates synchronously with the drive shaft 6. A lug member 54 formed into the horseshoe shape is press-fitted to the drive shaft 6 on the back side of the thrust plate 53. The lug member 54 is formed with an insertion hole 54 b so as to penetrate therethrough. According to the compressor in Embodiment 15, a link mechanism 55 is configured as described above. Other configurations are the same as in Embodiment 14.

In this compressor as well, the same effects and advantages as in Embodiment 14 are achieved.

Embodiment 16

The compressor in Embodiment 16 employs a member 56 and a plate-shaped arm 57. The member 56 includes a plate-shaped arm portion 56 a, a first pin portion 56 b extending from one end of the arm portion 56 a at a right angle with respect to the arm portion 56 a, and a second pin portion 56 c extending from the other end of the arm portion 56 a at a right angle with respect to the arm portion 56 a.

The arm 57 is formed with press-fitting holes 57 a and 57 b at both ends of the arm 57 so as to penetrate therethrough. The arm 57 includes an outer surface 57 d and an inner surface 57 e facing back to back in pair.

The arm portion 56 a is a portion which may serve as any one of the first intermediate arm and the second intermediate arm, and has the outer surface 56 d and the inner surface 51 e facing back to back in pair. The first pin portion 56 b is a portion which may serve as any one of the lug-side pin and the swash-plate-side pin, and is formed to have a diameter which is press-fitted into the press-fitting holes 57 a and 57 b of the arm 57. The second pin portion 56 c is a portion which may serve as the other one of the lug-side pin and the swash-plate-side pin and is formed to have a diameter which is press-fitted into the press-fitting holes 57 a and 57 b of the arm 57. The compressor in Embodiment 16, a link mechanism 58 is configured as described above. Other configurations are the same as in Embodiment 10.

In this compressor, a sub-assembly is obtained by assembling the member 56 and the arm 57 with the drive shaft 6, the thrust plate 53, the lug member 54, and the swash plate 11. Accordingly, the number of components is reduced, and the number of times of press-fitting operations is reduced, so that the reduction of manufacturing cost may be realized. Other effects and advantages are the same as in Embodiment 10.

Embodiment 17

According to the compressor in Embodiment 17, as shown in FIG. 25 and FIG. 26, a thrust plate 59 is formed with an insertion hole 59 a so as to penetrate therethrough and a drive shaft 61 is inserted into the insertion hole 59 a. In this manner, the thrust plate 59 is clearance-fitted to the drive shaft 61.

The drive shaft 61 is formed with a swelled portion 61 a as a lug member having a large diameter on the back side of the portion where the thrust plate 59 is clearance-fitted. The swelled portion 61 a is formed with pin portions 61 b and 61 c projecting therefrom orthogonally to a center axis O in the direction away from each other. According to the compressor in Embodiment 17, a link mechanism 62 is configured as described above. Other configurations are the same as in Embodiment 10.

In this compressor, the sub-assembly is obtained by assembling the drive shaft 61, the first and second intermediate arms 21 and 22, the swash plate 11, and the swash-plate-side pin 24. Accordingly, the number of components is reduced, and the number of times of press-fitting operation is reduced, so that the reduction of manufacturing cost is realized. The swash plate 11, the swash plate arm 11 b, and the swash-plate-side pin 24 may be integrally provided.

Embodiment 18

According to the compressor in Embodiment 18, as shown in FIG. 27, a thrust plate 63 is formed with a press-fitting hole 63 a so as to penetrate therethrough, and the drive shaft 61 is press-fitted to the press-fitting hole 63 a. The press-fitting hole 63 a constitutes part of the swelled portion 61 a. According to the compressor in Embodiment 18, a link mechanism 64 is configured as described above. Other configurations are the same as in Embodiment 17.

In this compressor as well, the same advantages and effects as the Embodiment 17 are achieved. The swash plate 11, the swash plate arm 11 b, and the swash-plate-side pin 24 may be integrated.

Embodiment 19

According to the compressor in Embodiment 19, as shown in FIG. 28, a lug member 81 press-fitted to the drive shaft 6 is formed into a parallelepiped shape, and both side surfaces are parallel surfaces 81 a extending in parallel to each other so as to face back to back. The lug member 81 is formed with an insertion hole 81 b which is orthogonal to the both parallel surfaces 81 a on the side of the top dead center so as to penetrate therethrough. The insertion hole 81 b is formed to have a diameter slightly larger than that of the lug-side pin 23. Other configurations are the same as in Embodiment 18.

When the lug-side pin 23 is away from the center axis O of the drive shaft 6, the lug member 81 may be provided separately from the drive shaft 6, so that upsizing of the components is avoided. Other effects and advantages are the same as in Embodiment 18.

Embodiment 20

According to the compressor in Embodiment 20, as shown in FIG. 29, a disk-shaped lug member 65 is press-fitted to the drive shaft 6. The lug member 65 is provided with the thrust bearing 5 d on the front surface thereof for receiving a thrust load between the lug member 65 and the front housing 2 (see FIG. 1), and is provided with a lug arm 65 a which projects toward the swash plate 11 on the back surface thereof.

The lug arm 65 a is formed with an insertion hole 65 b so as to penetrate therethrough, and the swash plate arm 11 b is formed with the insertion hole 11 d so as to penetrate therethrough. The lug-side pin 23 is inserted into the insertion hole 65 b, and the swash-plate-side pin 24 is inserted into the insertion hole 11 d. The first and second intermediate arms 21 and 22 are joined while being rotatably supported by the lug arm 42 a and the swash plate arm 11 b via the lug-side pin 23 and the swash-plate-side pin 24 and clamping the lug arm 42 a and the swash plate arm 11 b via the lug-side pin 23 and the swash-plate-side pin 24 so as to allow the sliding movement.

A gap g1 between the insertion hole 65 b of the lug arm 65 a and the lug-side pin 23 is set to be smaller than a gap g2 between the first and second intermediate arms 21 and 22 and the lug arm 65 a. The gap g1 between the insertion hole 11 d of the swash plate arm 11 b and the swash-plate-side pin 24 is set to be smaller than the gap g2 between the first and second intermediate arms 21 and 22 and the swash plate arm 11 b. According to the compressor in Embodiment 20, a link mechanism 66 is configured as described above. Other configurations are the same as in Embodiment 9.

In this compressor, the torque transmitted from the lug member 65 is preferably received by the lug-side pin 23, and the first and second intermediate arms 21 and 22 are hardly abutted against the edge portion of the lug member 65 at corners. The moment transmitted from the swash plate 11 is preferably received by the swash-plate-side pin 24, and the first and second intermediate arms 21 and 22 are hardly abutted against the edge portion of the swash plate arm 11 b at corners.

Accordingly, the distortion is prevented further reliably. Other effects and advantages are the same as in Embodiment 1.

Embodiment 21

According to the compressor in Embodiment 21, as shown in FIG. 30, a thrust plate 67 and a lug member 68 are press-fitted to the drive shaft 6. The thrust plate 67 is formed of aluminum-based material for reducing the weight. Since the lug member 68 rotates synchronously with the drive shaft 6, and transmits a torque to the swash plate 11 via a link mechanism 71, it is formed of iron-based material as the drive shaft 6. The lug-side pin 23 extends orthogonally to the center axis O of the drive shaft 6.

A washer 69 formed of vibration-control metal alloy is provided between the thrust plate 67 and the lug member 68. One supporting portion 11 g is projected from the surface of the swash plate 11 on the side of the lug member 68 and on the side of the bottom dead center toward the washer 69, and the supporting portion 11 g is adapted to come into abutment with the rear surface of the washer 69 when the swash plate 11 is inclined to the maximum angle of inclination. According to the compressor in Embodiment 21, the link mechanism 71 is configured as described above. Other configurations are the same as in Embodiment 1.

In this compressor, even though the relative rotation occurs between the lug member 68 and the thrust plate 67, the both members may be effectively prevented from being worn. Since the supporting portion 11 g of the swash plate 11 comes into abutment with the washer 69, even though the relative rotation occurs between the thrust plate 67 and the swash plate 11, the both members may be prevented from being worn. Since the washer 69 is formed of the vibration-control metal alloy, the noises or the vibrations may be reduced.

Embodiment 22

According to the compressor in Embodiment 22, as shown in FIG. 31, a thrust plate 72 is formed with an insertion hole 72 a so as to penetrate therethrough, and the drive shaft 6 is inserted into the insertion hole 72 a. In this manner, the thrust plate 72 is clearance-fitted to the drive shaft 6. The lug member 68 is press-fitted to the drive shaft 6. According to the compressor in Embodiment 22, a link mechanism 73 is configured as described above. Other configurations are the same as in Embodiment 21.

In this compressor as well, the effects and advantages as in Embodiment 21 are achieved.

Embodiment 23

According to the compressor in Embodiment 23, as shown in FIG. 32 and FIG. 33, a thrust plate 75 is formed with an insertion hole 75 a so as to penetrate therethrough, and a drive shaft 74 is inserted into the insertion hole 75 a. In this manner, the thrust plate 75 is clearance-fitted to the drive shaft 74.

The drive shaft 74 is formed with a swelled portion 74 a as a lug member having a large diameter on the back side of the portion where the thrust plate 75 is clearance-fitted. The swelled portion 74 a is formed with a press-fitting hole 74 b which extends orthogonally to the center axis O so as to penetrate therethrough. The swash plate arm 11 b of the swash plate 11 is formed with a press-fitting hole 11 h extending in parallel to the press-fitting hole 74 b.

The first and second intermediate arms 21 and 22 are formed with through holes 21 e, 21 f, 22 e, and 22 f at both ends thereof so as to penetrate therethrough. The press-fitting holes 74 b and 11 h each have a press-fitting margin with respect to the lug-side pin 23 and the swash-plate-side pin 24, and the insertion holes 21 e, 21 f, 22 e, and 22 f are formed to have a diameter slightly larger than those of the lug-side pin 23 and the swash-plate-side pin 24. In this manner, in this compressor, the lug-side pin 23 is loosely fitted to the first and second intermediate arms 21 and 22 while being press-fitted into the swelled portion 74 a, and the swash-plate-side pin 24 is loosely fitted to the first and second intermediate arms 21 and 22 while being press-fitted into the swash plate arm 11 b.

The thrust plate 75 is formed with side walls 75 b and 75 c positioned at both ends of the lug-side pin 23. The inner surfaces of the both side walls 75 b and 75 c serve as guiding surfaces 75 d and 76 e for guiding the outer surfaces 21 a and 22 a of the first and second intermediate arms 21 and 22. The guiding surfaces 75 d and 75 e of the side walls 75 b and 75 c prevent the first and second intermediate arms 21 and 22 from coming apart from the lug-side pin 23 and the swash-plate-side pin 24. According to the compressor in Embodiment 23, a link mechanism 76 is configured as described above. Other configurations are the same as in Embodiment 10.

In this compressor, even though the moment acting on the swash plate 11 is large, the first and second intermediate arms 21 and 22 loosely fitted to the lug-side pin 23 and the swash-plate-side pin 24 are able to transmit the thrust load stably from the swash plate arm 11 b to the swelled portion 74 a. Since the side walls 75 b and 75 c of the thrust plate 75 reinforce the first and second intermediate arms 21 and 22, the thickness of the first and second intermediate arms 21 and 22 is reduced, so that weight reduction and improvement of the balance of rotation of the link mechanism 75 are enabled. Other effects and advantages are the same as in Embodiment 1.

Embodiment 24

According to the compressor in Embodiment 24, as shown in FIG. 34, first and second intermediate arms 77 and 78 configured in such a manner that the thickness around the lug-side pin 23 is larger than the thickness around the swash-plate-side pin 24 in terms of the direction of rotation of the drive shaft 74 are employed. In the compressor in Embodiment 24, a link mechanism 79 is configured as described above. Other configurations are the same as in Embodiment 23.

In this compressor, the lug-side pin 23 is loosely fitted to the first and second intermediate arms 77 and 78 by a length larger than that of the swash-plate-side pin 24, so that the first and second intermediate arms 77 and 78 are hardly inclined in the direction of rotation of the swash plate 11. Therefore, the intermediate arms 77 and 78 hardly come apart from the lug-side pin 23 and the swash-plate-side pin 24 in association with the effect of the side walls 75 b and 75 c, so that rattling of the link mechanism 79 is reduced, and the operability thereof is stabilized. Therefore, the noises or the abnormal sounds of the compressor are reduced. Other effects and advantages are the same as in Embodiment 23.

Embodiment 25

According to the compressor in Embodiment 25, as shown in FIG. 35, the thrust plate 59 is formed with the insertion hole 59 a, and a drive shaft 82 is inserted into the insertion hole 59 a. In this manner, the thrust plate 59 is clearance-fitted to the drive shaft 82.

The drive shaft 82 is formed with a swelled portion 82 a as a lug member having a large diameter on the back side of a portion where the thrust plate 59 is clearance-fitted. The swelled portion 82 a is formed with a bearing hole 82 b so as to penetrate therethrough. The swash plate arm 11 b of the swash plate 11 is formed with a bearing hole 82 c so as to penetrate therethrough extending in parallel to the bearing hole 82 b.

Plane bearings 83 and 84 are press-fitted into the bearing holes 82 b and 82 c, and the lug-side pin 23 and the swash-plate-side pin 24 are rotatably and slidably stored in the plane bearings 83 and 84. The lug-side pin 23 and the swash-plate-side pin 24 are press-fitted into the first and second intermediate arms 21 and 22. According to the compressor in Embodiment 25, a link mechanism 85 is configured as described above. Other configurations are the same as in Embodiment 10.

In this compressor, sliding property between the swelled portion 82 a and the lug-side pin 23 and between the swash plate arm 11 b and the swash-plate-side pin 24 is increased, and the operability and the quietness of the link mechanism 85 is improved. Other effects and advantages are the same as in Embodiment 1. It is also possible to employ a bearing using a roller or a ball instead of the plane bearings 83 and 84.

Embodiment 26

According to the compressor in Embodiment 26, as shown in FIG. 36, the thrust plate 59 is clearance-fitted to a drive shaft 86. The drive shaft 86 is formed with a swelled portion 86 a as a lug member having a large diameter on the back side of a portion where the thrust plate 59 is clearance-fitted. The swelled portion 86 a is formed with a press-fitting hole 86 b so as to penetrate therethrough. The swash plate arm 11 b of the swash plate 11 is formed with the press-fitting hole 11 h so as to penetrate therethrough extending in parallel to the press-fitting hole 86 b.

The first and second intermediate arms 87 and 88 are formed with bearing holes 87 a, 87 b, 88 a, and 88 b so as to penetrate therethrough at both ends thereof. Plane bearings 89, 91, 92 and 93 are press-fitted into the bearing holes 87 a, 87 b, 88 a, and 88 b, and the lug-side pin 23 and the swash-plate-side pin 24 are rotatably and slidably stored in the plane bearings 89, 91, 92, and 93. The lug-side pin 23 and the swash-plate-side pin 24 are press-fitted into the swelled portion 86 a and the swash plate arm 11 b. According to the compressor in Embodiment 26, a link mechanism 94 is configured as described above. Other configurations are the same as in Embodiment 10.

In this compressor as well, the same effects and advantages as in Embodiment 25 are achieved. It is also possible to employ a bearing using a roller or a ball instead of the plane bearing 89, 91, 92, and 93.

Although the description has been given on the basis of Embodiments 1 to 26 thus far, the present invention is not limited to Embodiments 1 to 26, and modifications may be made without departing the scope of the invention.

For example, the rotatable supporting of the rug-side axis and the rotatable supporting of the swash-plate-side axis is achieved by bolts.

When the refrigerant is CO₂, if it is impossible to position the lug-side axis on the side of the bottom dead center, the lug-side axis may intersect the center axis O of the drive shaft, and may be positioned on the side of the top dead center position of the swash plate.

According to the compressor of the present invention, the lug member may be integrated with the drive shaft or may be provided separately and fixed to the drive shaft. The width of the lug member is preferably the same as the width of the swash plate arm.

When the lug member is provided integrally with the drive shaft, a part of the drive shaft may be formed into the lug member. When the lug-side pin and the drive shaft are provided separately, the lug member integrated with the drive shaft corresponds to a portion having an insertion hole for inserting the lug-side pin or a press-fitting hole for press-fitting the lug-side pin. The lug member integrated with the drive shaft may have the same diameter as an adjacent portion of the drive shaft, or may be different therefrom, for example, may be larger than that. When employing the lug member integrated with the drive shaft, control of a press-fitting margin required for press-fitting the lug member to the drive shaft may be eliminated, and reduction of the number of components is realized.

When the lug member is provided separately from the drive shaft, the lug member may be fixed to the drive shaft by press-fitting or the like. When the lug-side pin and the drive shaft are provided separately, the lug member provided separately from the drive shaft includes the insertion hole for inserting the lug-side pin or the press-fitting hole for press-fitting the lug-side pin. When the lug member provided separately from the drive shaft is employed, the productivity of the drive shaft is improved.

The joint of the first and second intermediate arms by the lug-side pin and the joint of the first and second intermediate arms by the swash-plate-side pin may be achieved by means such as press-fitting or welding.

Preferably, the lug-side pin is loosely fitted to the lug member and is press-fitted into the first intermediate arm and the second intermediate arm, and the swash-plate-side pin is loosely fitted to the swash plate arm and is press-fitted into the first intermediate arm and the second intermediate arm.

In this case, assembly of the link mechanism is achieved in the following manner.

First of all, the lug member and the swash plate arm are prepared. The lug member is formed with an insertion hole having a slightly larger diameter than that of the lug-side pin, and the swash plate arm is formed with an insertion hole having a slightly larger diameter than that of the swash-plate-side pin. The first and second intermediate arms are formed with press-fitting holes each having a press-fitting margin with respect to the lug-side pin, and press-fitting holes each having a press-fitting margin with respect to the swash-plate-side pin.

Then, the lug-side pin and the swash-plate-side pin are press-fitted into the respective press-fitting holes of the first intermediate arm and, in this state, the lug-side pin and the swash-plate pin are press-fitted into the press-fitting holes of the second intermediate arm while inserting the lug-side pin and the swash-plate-side pin into the insertion holes of the lug member and the swash-plate arm. When the first and second intermediate arms clamp the lug member or the swash plate arm, the press-fitting operation is ended. In this manner, the first and second intermediate arms are joined to each other while being preferably guided with reduced dimensional tolerance with respect to the lug member and the swash plate arm. Means for preventing the lug-side pin and the swash-plate-side pin from coming off is not necessary. Accordingly, the high productivity is demonstrated.

In this case, since the first intermediate arm is brought into contact with the lug member and the swash plate arm at a high pressure, the first intermediate arm is preferably prevented from being fixed with the lug member and the swash plate arm by applying organic liquid such as grease. A fine gap is secured between the first intermediate arm and the lug member and the swash plate arm by the organic liquid, and the organic liquid may be removed easily by heating after assembly. It is also possible to press-fit the lug-side pin and the swash-plate-side pin into the respective press-fitting holes of the second intermediate arm and then, in this state, press-fit the lug-side pin and the swash-plate-side pin into the press-fitting holes of the first intermediate arm.

Alternatively, by forming the lug-side pin and the swash-plate-side pin to have the same diameter, the insertion hole for the lug-side pin and the insertion hole for the swash-plate-side pin to have the same diameter, and the press-fitting hole for the lug-side pin and the press-fitting hole for the swash-plate-side pin to have the same diameter, the higher productivity is demonstrated. Manufacturing the first and second intermediate arms so as not to have the difference between the front and the rear or between the right side and the back side also leads to the high-productivity.

According to the compressor in the present invention, preferably, the swash-plate-side axis is positioned on the side of the top dead center position of the swash plate, and the lug-side axis is closer to the drive shaft than that of the swash-plate-side axis.

By rotatably supporting the intermediate arms as descried above, the link mechanism approaches the drive shaft, and hence the lubricating oil in the crank chamber is hardly stirred, and hence is hardly be heated. Therefore, the viscosity of the lubricating oil is hardly lowered, and a high sliding property is secured. A rubbery material such as a sealing member is hardly deteriorated due to the heat of the lubricating oil, so that the high durability is demonstrated. The side of the top dead center position of the swash plate means a half circumference of the swash plate including the top dead center position of the swash plate.

When the intermediate arms are rotatably supported in this manner, the center of gravity of the intermediate arms are low and hence a centrifugal force is reduced. Therefore, a load in the direction to increase the angle of inclination of the swash plate at a high velocity is reduced, and hence the angle of inclination of the swash plate is easily controlled. A thrust load applied from the swash plate acts on the portion near the drive shaft, and hence noises or abnormal sounds are reduced.

When the lug-side axis is positioned near the drive shaft in comparison with the swash-plate-side axis, the lug-side axis may intersect the center axis of the drive shaft and may be positioned on the side of the top dead center position of the swash plate. However, it is preferable to be positioned on the side of the bottom dead center position of the swash plate.

Accordingly, since the balance of rotation of a sub-assembly including the drive shaft (lug member), the link mechanism, and the swash plate is easily achieved, the weight portion of the lug member is not necessary or the size of the weight portion of the lug member may be reduced, so that reduction in weight and number of machining processes is achieved. The side of the bottom dead center position of the swash plate means the half circumference of the swash plate including the bottom dead center position of the swash plate.

According to the compressor in the present invention, a thrust plate which rotates synchronously with the drive shaft, and a thrust bearing provided between the thrust plate and the housing may be provided in the housing. In this case, the thrust plate and the lug member both may constitute an integral lug plate which rotates synchronously with the drive shaft.

Since the lug plate as described above can be obtained relatively easily by improving the lug plate with the lug arm used in the related art, it contributes to the reduction of manufacturing cost of the compressor in the present invention.

The lug plate as described above may be provided with a supporting portion which supports the side opposite from the swash plate of at least one of the first intermediate arm and the second intermediate arm when the swash plate is inclined to a maximum angle of inclination. Therefore, the supporting portion of the lug plate receives a compression reaction force transmitted from the piston to the swash plate, so that the deformation of the link mechanism is prevented and hence the superior durability is demonstrated. With this lug plate, the supporting portion is preferably positioned on the side of the top dead center position of the swash plate.

Since the compression reaction force acts on the side of the top dead center as a large load, downsizing of the intermediate arms and the superior durability are achieved by receiving the large load by the supporting portion on the side of the top dead center.

The link mechanism is required to have ambivalent characteristics. The ambivalent characteristics are, for example, (1) demand for weight reduction, (2) improvement in sounds caused by torque variations due to the increase in inertial mass, and (3) reduction of the inertial mass for protecting the torque limiter from the torque variation when the clutchless compressor is connected to an engine which is subjected to large torque variations. In order to accommodate these requests independently by the link mechanism in the related art in which the lug plate including the thrust plate and the lug member integrated therewith is employed, there arise disadvantages such that the type of the link mechanisms increases, additional production facility is required, and the manufacturing effects is lowered.

In this regard, according to the compressor in the present invention, when the thrust plate which rotates synchronously with the drive shaft, and the thrust bearing provided between the thrust plate and the housing are provided in the housing, the thrust plate is preferably in abutment with the lug member or the intermediate arms.

In other words, the thrust plate and the lug member are preferably provided separately. In this case, even when the thrust plate is secured to the drive shaft by being press-fitted, or even when it is clearance-fitted to the drive shaft, the above-described requests are met independently simply by changing the material of mainly the thrust plate.

In other words, when the lug-side axis is positioned on the side of the bottom dead center position of the swash plate, the swash-plate-side axis is positioned on the side of the top dead center position of the swash plate, and the thrust plate and the lug member are provided separately, the good rotational balance of the sub-assembly including the drive shaft, the thrust plate, the lug member, the link mechanism, and the swash plate is achieved, so that elimination of the weight portion from the thrust plate or reduction of the size of the weight portion provided on the thrust plate are possible. When the thrust plate and the lug member are provided separately, and the thrust plate is in abutment with the lug member or the intermediate arms, the thrust plate does not have to have a function to rotate the swash plate synchronously. Therefore, the link mechanism does not involve the thrust plate, and hence the strength or hardness of the sliding portion which is essential for the link mechanism is not necessary any longer to the thrust plate. From these reasons, the demands as described above are met by changing only the material of the thrust plate while keeping the same shape.

For example, when quietness is required for the compressor such as the case in which the compressor is used in an air conditioning system for a high-grade vehicle, the torque variations of the compressor are absorbed by the thrust plate. In this case, the thrust plate is formed into a large size with a high-mass material such as iron-based metal or copper-based metal. On the other hand, when the compressor is used in an air conditioning system for a relatively small vehicle and the weight reduction is required, the thrust plate is downsized with a low-mass material such as aluminum-based metal. When the clutchless compressor is connected to an engine which is subjected to large torque variations, a torsion torque which acts on a power transmitting member between the engine and the compressor is excessively increased. In this case, the thrust plate is downsized as much as possible to reduce the torsion torque, so that the torque limiter is protected.

When the thrust plate and the lug member are provided separately, the thrust plate is preferably clearance-fitted to the drive shaft.

In this case, vibrations or abnormal sounds due to the inclination of the seat of the housing which receives the thrust bearing and the tolerance in perpendicularity between the thrust plate and the drive shaft may also be resolved.

Since the compression reaction force acts on the position deviated from the drive shaft, when the thrust plate is secured to the drive shaft, a thrust bearing having a large load capacity which resists a deviated abutment must be employed. In this case, the manufacturing cost of the compressor is significantly increased and, in addition, upsizing of the compressor is resulted due to increase in diameter of the thrust bearing. In this regard, when the thrust plate is clearance-fitted to the drive shaft, the thrust plate by itself is inclined by the compression reaction force and hence the deviated abutment against the thrust bearing is avoided. Therefore, the thrust bearing having a small load capacity may be employed, and the diameter of the thrust plate may be reduced, so that reduction in manufacturing cost of the compressor and downsizing of the compressor are realized. When the thrust plate is clearance-fitted to the drive shaft, the moment acting on the swash plate is received by a radial bearing which supports the drive shaft on the housing. Therefore, the thrust load is received at the substantially center of the thrust plate, and vibrations or abnormal sounds generated at the bearing are reduced. When the reduction in diameter of the thrust plate and the thrust bearing is achieved, the lubricating oil in the crank chamber is hardly stirred, and hence heat generation of the lubricating oil is restrained.

When the lug member provided integrally with the drive shaft is employed while employing the thrust plate which is clearance-fitted to the drive shaft, a labor to machine the seat of the thrust plate after having assembled the sub-assembly including the drive shaft (lug member), the thrust plate, the link mechanism, and the swash plate is eliminated.

In order to clearance-fit the thrust plate to the drive shaft while allowing synchronous rotation with the drive shaft, the thrust plate and the drive shaft may be fitted via a spline or a key. In this case, when assembling the sub-assembly, the thrust plate may be fixed to the drive shaft by a snap ring or the like. Even though the drive shaft and the thrust plate are not spline fitted, if the lug member comes into abutment with the thrust plate by a thrust load which is transmitted via the piston or the like, the thrust plate rotates synchronously with the drive shaft.

The thrust plate is preferably formed of vibration-control metal alloy.

The vibration-control metal alloy converts vibration energy into heat by molecular friction in the interior thereof and absorbs the vibrations. The vibration-control metal alloy has a vibration absorbing characteristic with low degree of dependence on the temperature, and has a high damping capacity. In addition, the vibration-control metal alloy is superior in shape flexibility and in durability. Therefore, when changing the material of the thrust plate on the basis of the demands as described above, the vibrations transmitted from the piston side are absorbed by the thrust plate so that the vibrations of the entire compressor is restrained with the thrust plate formed of the vibration-control metal alloy. The vibration-control metal alloy which may be employed includes (1) ferromagnetic vibration-control metal alloy like Fe—Cr—Al, Fe—Cr—Al—Mn, Fe—Cr—Mo, Co—Ni, or Fe—Cr, (2) Al—Zn vibration-control metal alloy of a composite type, (3) vibration-control metal alloy of a transfer type like Mn—Cu or Cu—Mn—Al, and (4) vibration-control metal alloy of a twin crystal type like Cu—Zn—Al, Cu—Al—Ni, or Ni—Ti.

It is also possible to provide a supporting portion for supporting the side opposite from the swash plate of at least one of the first intermediate arm and the second intermediate arm when the swash plate is inclined to a maximum angle of inclination on the lug member separate from the thrust plate. The compression reaction force to be transmitted from the piston to the swash plate by the supporting portion of the lug member is received by the thrust plate to prevent the link mechanism from being deformed, so that the superior durability is demonstrated. In the case of this lug member as well, the supporting portion is preferably positioned on the side of the top dead center position of the swash plate.

Since the compression reaction force acts on the side of the top dead center as a large load, downsizing of the intermediate arms and the superior durability are realized by receiving the large load by the supporting portion on the side of the top dead center.

When employing the thrust plate clearance-fitted to the drive shaft, the thrust plate is preferably formed with side walls having guiding surfaces for guiding the outer surfaces of the first intermediate arm and the second intermediate arm.

The vibrations or abnormal sounds are eliminated irrespective of the tolerance such as the positional relation or the symmetry of the thrust plate and the drive shaft or the lug member only by forming the both guiding surfaces of the both side walls with high degree of accuracy. Since the side walls of the thrust plate reinforce the first and second intermediate arms, the thickness of the first and second intermediate arms may be reduced, so that weight reduction of the link mechanism and improvement of the balance of rotation are enabled. Fixation of the lug-side pin or the swash-plate-side pin and the first and second intermediate arms via the press-fitting is no longer necessary, and hence assembleability is improved.

The intermediate arms may be formed with the weight portion on the side of the bottom dead center position of the swash plate.

Accordingly, the rotational balance is achieved. The weight portion is preferably positioned so as not to be away from the drive shaft too much in the radial direction to prevent the lubricating oil in the crank chamber from being stirred much.

A spring having an urging force for urging the swash plate in the direction to reduce the angle of inclination of the swash plate may be provided between the lug member and the intermediate arms, between the thrust plate and the intermediate arms, or between the intermediate arms and the swash plate arm.

In this case, the swash plate is urged by the spring in the direction in which the angle of inclination is reduced, and reduction of a torque for activation is achieved. In the general compressor, a coil spring is provided around the drive shaft at a position between the lug plate and the swash plate as the spring for urging the swash plate in the direction in which the angle of inclination is reduced as described above. However, when such the coil spring is employed in the compressor in the present invention, positioning of the lug-side axis on the side of the bottom dead center position of the swash plate becomes difficult. In this regard, positioning of the lug-side axis on the side of the bottom dead center position of the swash plate is facilitated by providing the spring between the lug member and the intermediate arms, between the thrust plate and the intermediate arms, or between the intermediate arms and the swash plate arm. As the spring described above which may be employed here includes a leaf spring and a torsion coil spring.

A run-off for avoiding distortion caused by the first intermediate arm and the second intermediate arm are preferably formed on at least one of the lug member and the swash plate arm.

According to the compressor in the present invention, the first and second intermediate arms are integrated, distortion hardly occurs from their original property. Even when there is a possibility of occurrence of the slight distortion due to the accumulated tolerance, the distortion caused by the first and second intermediate arms is avoided by forming the run-off on at least one of the lug member and the swash plate arm. At least one of the lug member and the swash plate arm is reduced in weight by the formation of the run-off, and hence the balance of rotation is easily achieved.

The gap between the lug member and the lug-side pin is preferably smaller than the gap between the first and second intermediate arms and the lug member.

In this case, the torque transmitted from the lug member is preferably received by the lug-side pin, and the first and second intermediate arms are hardly abutted against the edge portion of the lug member at corners. Accordingly, the distortion is prevented further reliably.

The gap between the swash plate arm and the swash-plate-side pin is preferably smaller than the gap between the first and second intermediate arms and the swash plate arm.

In this case, the moment transmitted from the swash plate is preferably received by the swash-plate-side pin, and the first and second intermediate arms are hardly abutted against the edge portion of the swash plate arm at corners. Accordingly, the distortion is prevented further reliably.

One of the lug-side pin and the swash-plate-side pin may be integrated with the first intermediate arm, and the other one of the lug-side pin and the swash-plate-side pin may be integrated with the second intermediate arm.

In this case, a sub-assembly is obtained by assembling a member in which the one of the lug-side pin and the swash-plate-side pin and the first intermediate arm are integrated, and a member in which the other one of the lug-side pin and the swash-plate-side pin and the second intermediate arm are integrated with the drive shaft, the lug member, the swash plate, or the like. Accordingly, the number of components is reduced, and the number of times of press-fitting operation is reduced, so that the reduction of manufacturing cost is achieved. By employing the lug-side pin and the swash-plate-side pin having the same diameter and the same length, and the first intermediate arm and the second intermediate arm formed not to have the difference between the front and the rear, the member in which the one of the lug-side pin and the swash-plate-side pin and the first intermediate arm are configured, and the member in which the other one of the lug-side pin and the swash-plate-side pin and the second intermediate arm are configured only by members in which the pin and the arm are integrated.

The lug-side pin and the swash-plate-side pin and one of the first intermediate arm and the second intermediate arm may be integrated.

In this case, the sub-assembly is obtained by assembling the member in which the lug-side pin and the swash-plate-si-de pin and the one of the first intermediate arm and the second intermediate arm are integrated, and the other one of the first intermediate arm and the second intermediate arm with the drive shaft, the lug member, and the swash plate or the like. Accordingly, the number of components is reduced, and the number of times of press-fitting operation is reduced, so that the reduction of manufacturing cost is achieved. By employing the lug-side pin and the swash-plate-side pin having the same diameter and the same length, and the first intermediate arm and the second intermediate arm formed not to have the difference between the front and the rear, the member in which the lug-side pin and the swash-plate-side pin and the one of the first intermediate arm and the second intermediate arm are integrated may be assembled easily.

At least one of the group of the drive shaft, the lug member and the lug-side pin, and the group of the swash plate, the swash plate arm and the swash-plate-side pin may be integrated. In other words, the drive shaft, the lug member, and the lug-side pin may be integrated, and the swash plate, the swash plate arm, and the swash-plate-side pin may be integrated.

When the drive shaft, the lug member, and the lug-side pin are integrated, the sub-assembly is obtained by assembling the member in which the drive shaft, the lug member, and the lug-side pin are integrated, the first and second intermediate arms, the swash plate, and the swash-plate-side pin. When the swash plate arm and the swash-plate-side pin are integrated, the sub-assembly is obtained by assembling the member in which the swash plate arm and the swash-plate-side pin are integrated, the first and second intermediate arms, the drive shaft, the lug-side member, the lug-side pin, and on the like. Accordingly, the number of components is reduced, and the number of times of press-fitting operation is reduced, so that the reduction of manufacturing cost is achieved.

A washer is preferably provided between the lug member and the thrust plate.

In this case, even though the relative rotation occurs between the lug member and the thrust plate, the both members are prevented from being worn. When the washer is formed of the vibration-control metal alloy, the noises or the vibrations are reduced. It is also possible to form the supporting portion which defines the maximum angle of inclination of the swash plate on the swash plate so that the supporting portion comes into abutment with the washer.

Since the lug member rotates synchronously with the drive shaft and transmits the torque to the swash plate via the link mechanism, the lug member is preferably formed of an iron-based material like the drive shaft. In contrast, the thrust plate may be formed of the aluminum-based material for weight reduction. In the case of this combination, the washer between the lug member and the thrust plate effectively prevents the thrust plate from being worn.

Preferably, the lug-side pin is loosely fitted to the first intermediate arm and the second intermediate arm while being press-fitted into the lug member, the swash-plate-side pin is loosely fitted to the first intermediate arm and the second intermediate arm while being press-fitted into the swash plate arm, and the first intermediate arm and the second intermediate arm are prevented from coming apart from the lug-side pin and the swash-plate-side pin.

In this case, the link mechanism may be assembled as follows.

First of all, the lug member and the swash plate arm are prepared. The lug member is formed with a press-fitting hole having a press-fitting margin with respect to the lug-side pin in advance, and the swash plate arm is formed with a press-fitting hole having a press-fitting margin with respect to the swash-plate-side pin in advance. The first and second intermediate arms each are formed with an insertion hole having a diameter slightly larger than that of the lug-side pin, and an insertion hole having a diameter slightly larger than that of the swash-plate-side pin.

Then, the lug-side pin and the swash-plate-side pin are press-fitted into the respective press-fitting holes of the lug member and the swash plate arm and, in this state, the lug-side pin and the swash-plate-side pin are inserted into the respective insertion holes of the first intermediate arm and the second intermediate arm and, simultaneously, are prevented from coming apart. Side walls or a snap ring may be employed as a measure to prevent the means from coming apart. In this manner, the first and second intermediate arms are joined to each other while being preferably guided with reduced dimensional tolerance with respect to the lug member and the swash plate arm.

When loosely fitting the lug-side pin and the swash-plate-side pin to the first and second intermediate arms, the thrust plate which rotates synchronously with the drive shaft, and the thrust bearing provided between the thrust plate and the housing may be provided in the housing. Preferably, at least one of the thrust plate and the swash plate is formed with side walls having guiding surfaces for guiding the outer surface of the first intermediate arm and the outer surface of the second intermediate arm.

In this case, even when the moment which acts on the swash plate is large, the first and second intermediate arms loosely fitted to the lug-side pin and the swash-plate-side pin are able to stably transmits a thrust load from the swash plate arm to the lug member. Since the side walls of the thrust plate are able to reinforce the first and second intermediate arms, the thickness of the first and second intermediate arms may be reduced, so that weight reduction and improvement of the rotational balance of the link mechanism are enabled.

When loosely fitting the lug-side pin and the swash-plate-side pin to the first and second intermediate arms, the first and second intermediate arms are preferably such that the thickness around one of the lug-side pin and the swash-plate-side pin is larger than the thickness around the other one of those in the direction of rotation of the drive shaft.

In this case, the first and second intermediate arms are configured in such a manner that the one of the lug-side pin and the swash-plate-side pin is loosely fitted by a length longer than the other one of those, and hence the first and second intermediate arms are hardly inclined in the direction of rotation of the swash plate. Therefore, the first and second intermediate arms hardly come apart from the lug-side pin and the swash-plate-side pin, so that rattling of the link mechanism is reduced, and the operability thereof is stabilized. Therefore, the noises or the abnormal sounds of the compressor are reduced.

When the lug-side pin is loosely fitted to the lug member and the swash-plate-side pin is loosely fitted to the swash plate arm, a bearing is preferably provided at least one of between the lug member and the lug-side pin and between the swash plate arm and the swash-plate-side pin.

In this case, the sliding performance of at least one of between the lug member and the lug-side pin and between the swash plate arm and the swash-plate-side pin is improved, so that the operability and quietness of the link mechanism are improved.

The movement converting mechanism may include shoe sliding surfaces formed on front and rear outer peripheral surfaces of the swash plate, shoe receiving surfaces formed on the piston, and semispherical shoes provided between the shoe sliding surfaces and the shoe receiving surfaces. In this case, the swash plate arm is preferably formed so as to avoid a position vertically above the shoe sliding surface.

In this case, the shoe sliding surface is easily formed on the swash plate, so that the productivity is improved.

EXPLANATION OF INDUSTRIAL APPLICATION OF INVENTION

The present invention is applicable to an air-conditioning system for vehicles. 

1. A capacity-variable type swash plate compressor comprising: a housing having a cylinder bore; a drive shaft rotatably supported by the housing; a lug member which rotates synchronously with the drive shaft in the housing; a swash plate supported by the drive shaft so as to change in angle of inclination in the housing; a link mechanism provided between the lug member and the swash plate in the housing so as to allow the swash plate to change in the angle of inclination with respect to the drive shaft and prohibit the swash plate from rotating with respect to the drive shaft; a piston stored in the cylinder bore so as to be capable of a reciprocal movement; and a movement converting mechanism provided between the swash plate and the piston for converting the rocking movement of the swash plate into the reciprocal movement of the piston, wherein the link mechanism includes one swash plate arm projecting from the swash plate toward the lug member, and intermediate arms rotatably supported by the lug member so as to rotate about the lug-side axis extending orthogonally to a virtual plane defined by the center axis of the drive shaft and the top dead center position of the swash plate and rotatably supported by the swash plate arm about the swash-plate-side axis which extends in parallel to the lug-side axis, wherein the intermediate arms include a first intermediate arm and a second intermediate arm extending from the lug member side toward the swash plate side, and wherein the first intermediate arm and the second intermediate arm are joined while being rotatably supported by the lug member and the swash plate arm via a lug-side pin which constitutes the lug-side axis and a swash-plate-side pin which constitutes the swash-plate-side axis and clamping the lug member and the swash plate arm via the lug-side pin and the swash-plate-side pin so as to allow the sliding movement.
 2. The capacity-variable type swash plate compressor according to claim 1, wherein the lug-side pin is loosely fitted to the lug member and is press-fitted into the first intermediate arm and the second intermediate arm, and the swash-plate-side pin is loosely fitted to the swash plate arm and is press-fitted into the first intermediate arm and the second intermediate arm.
 3. The capacity-variable type swash plate compressor according to claim 1, wherein the swash-plate-side axis is positioned on the side of the top dead center position of the swash plate, and the lug-side axis is closer to the drive shaft than the swash-plate-side axis.
 4. The capacity-variable type swash plate compressor according to claim 3, wherein the lug-side axis is positioned on the side of the bottom dead center position of the swash plate.
 5. The capacity-variable type swash plate compressor according to claim 3, wherein a thrust plate which rotates synchronously with the drive shaft, and a thrust bearing provided between the thrust plate and the housing are provided in the housing, and wherein the thrust plate and the lug member both constitute an integral lug plate.
 6. The capacity-variable type swash plate compressor according to claim 5, wherein the lug plate is provided with a supporting portion which supports the side opposite from the swash plate of at least one of the first intermediate arm and the second intermediate arm when the swash plate is inclined to a maximum angle of inclination, and wherein the supporting portion is positioned on the side of the top dead center position of the swash plate.
 7. The capacity-variable type swash plate compressor according to claim 3, wherein the thrust-plate which rotates synchronously with the drive shaft, and the thrust bearing provided between the thrust plate and the housing are provided in the housing, and the thrust plate is in abutment with the lug member or the intermediate arms.
 8. The capacity-variable type swash plate compressor according to claim 7, wherein the thrust plate is clearance-fitted to the drive shaft.
 9. The capacity-variable type swash plate compressor according to claim 7, wherein the thrust plate is formed of vibration-control metal alloy.
 10. The capacity-variable type swash plate compressor according to any one of claims 7, wherein the lug member is provided with a supporting portion for supporting the side opposite from the swash plate of at least one of the first intermediate arm and the second intermediate arm when the swash plate is inclined to a maximum angle of inclination, and the supporting portion is positioned on the side of the top dead center position of the swash plate.
 11. The capacity-variable type swash plate compressor according to claim 8, wherein the thrust plate is formed with side walls having guiding surfaces for guiding the outer surface of the first intermediate arm and the outer surface of the second intermediate arm.
 12. The capacity-variable type swash plate compressor according to claim 1, wherein the intermediate arms are formed with a weight portion on the side of the bottom dead center position of the swash plate.
 13. The capacity-variable type swash plate compressor according to claim 5, wherein a spring having an urging force for urging the swash plate in the direction to reduce the angle of inclination of the swash plate is provided between the lug member and the intermediate arms, between the thrust plate and the intermediate arms, or between the intermediate arms and the swash plate arm.
 14. The capacity-variable type swash plate compressor according to claim 7, wherein a spring having an urging force for urging the swash plate in the direction to reduce the angle of inclination of the swash plate is provided between the lug member and the intermediate arms, between the thrust plate and the intermediate arms, or between the intermediate arms and the swash plate arm.
 15. The capacity-variable type swash plate compressor according to claim 1, wherein a run-off for avoiding distortion caused by the first intermediate arm and the second intermediate arm is formed on at least one of the lug member and the swash plate arm.
 16. The capacity-variable type swash plate compressor according to claim 2, wherein the gap between the lug member and the lug-side pin is smaller than the gap between the first and second intermediate arms and the lug member.
 17. The capacity-variable type swash plate compressor according to claim 2, wherein the gap between the swash plate arm and the swash-plate-side pin is smaller than the gap between the first and second intermediate arms and the swash plate arm.
 18. The capacity-variable type swash plate compressor according to claim 1, wherein one of the lug-side pin and the swash-plate-side pin is integrated with the first intermediate arm, and the other one of the lug-side pin and the swash-plate-side pin is integrated with the second intermediate arm.
 19. The capacity-variable type swash plate compressor according to claim 1, wherein the lug-side pin and the swash-plate-side pin and one of the first intermediate arm and the second intermediate arm is integrated.
 20. The capacity-variable type swash plate compressor according to claim 1, wherein at least one of the group of the drive shaft, the lug member and the lug-side pin, and the group of the swash plate, the swash plate arm and the swash-plate-side pin are integrated.
 21. The capacity-variable type swash plate compressor according to claim 7, wherein a washer is provided between the lug member and the thrust plate.
 22. The capacity-variable type swash plate compressor according to claim 1, wherein the lug-side pin is loosely fitted to the first intermediate arm and the second intermediate arm while being press-fitted into the lug member, the swash-plate-side pin is loosely fitted to the first intermediate arm and the second intermediate arm while being press-fitted into the swash plate arm, and wherein the first intermediate arm and the second intermediate arm are prevented from coming apart from the lug-side pin and the swash-plate-side pin.
 23. The capacity-variable type swash plate compressor according to claim 22, wherein the thrust plate which rotates synchronously with the drive shaft, and the thrust bearing provided between the thrust plate and the housing are provided in the housing, and wherein at least one of the thrust plate and the swash plate is formed with the side walls having the guiding surfaces for guiding the outer surface of the first intermediate arm and the outer surface of the second intermediate arm.
 24. The capacity-variable type swash plate compressor according to claim 22, wherein the first and second intermediate arms are such that the thickness around one of the lug-side pin and the swash-plate-side pin is larger than the thickness around the other one of those in the direction of rotation of the drive shaft.
 25. The capacity-variable type swash plate compressor according to claim 2, wherein a bearing is provided at least one of between the lug member and the lug-side pin and between the swash plate arm and the swash-plate-side pin.
 26. The capacity-variable type swash plate compressor according to any one of claims 1, wherein the movement converting mechanism includes shoe sliding surfaces formed on front and rear outer peripheral surfaces of the swash plate, shoe receiving surfaces formed on the piston, and semispherical shoes provided between the shoe sliding surfaces and the shoe receiving surfaces, and wherein the swash plate arm is formed so as to avoid a position vertically above the shoe sliding surface. 